1. Field of the Invention
The present invention relates to a printer for receiving input data from an external apparatus such as a host computer or the like, and printing the received data on, e.g., a paper sheet, and a data transfer control method for the printer.
2. Related Background Art
In a conventional printer, a control unit and a print mechanism unit are connected in hardware and software manners via a specific interface/protocol determined therebetween. Bit map image data (including byte map data) created by the control unit is transferred to the print mechanism unit via the interface in the form of the bit map data, and is printed by the print mechanism unit on, e.g., a paper sheet.
A user must correctly designate various kinds of print method information such as a print medium, a print mode, and the like.
However, with the advent of high-resolution printers, color printers, and the like, the transfer amount of bit map image data is increasing, and data transfer executed via the interface requires a much longer period of time than a normal memory access depending on the conditions of the protocol processing (including processing for determining and setting the status of signal lines, and the like), the data width, and the like.
For this reason, the increase in data amount increases the processing cost and time required for the data transfer from the control unit to the print mechanism unit in the printer, and such loads inevitably lower the performance of the entire printer.
In particular, when bit map image data in a single page is repetitively transmitted to the print mechanism unit by, e.g., a copy function in the printer, since the drawing processing of a bit map has been completed, only the transfer processing time required for the single data accounts for most of the total processing time, and time for another input data processing cannot be assured.
In the above-mentioned prior art, a user designates a proper combination of a type of paper sheet and a print mode using an operation panel or control commands. In order to correctly designate a proper combination, the user must look up the combination in a manual. If the user designates a mis-matched combination of a paper sheet and a print mode, a print result that he or she intended cannot be obtained.